Variables

1
Variables Chapter 10
2
Mutable Variables

• A piece of storage that holds a value (piece of
  information) while a program is running
• Name
• Unique
• Cannot be changed
• Data Type
• Can be changed (mutable)

3
Use of Variables

• Keep track of Values
• Counters
• Number of times something has happened
• Keep track of Changes
• Position
• Color

4
In ALICE

• Variable is a property that can be directly
  changed using a SET method
• Added to the PROPERTIES list
• Not directly visible within the ALICE world

5
Example

• Timer
• Begin at Specified Time
• Count down to 0
• Scorekeeper
• Begins at zero
• Increases the score when a player scores a point

6
Sample Code

• Create a world using the Hopping Bunny. The
  bunny should hope for 10 seconds with a timer
  counting down from 10 to 0.